The TARDIS lands on Pluto in the far future, where the Doctor is
astonished to find the planet inhabited by humans and heated by a number
of miniature suns. He, Leela and K·9 discover that the human race has
been moved off Earth to do the bidding of the Company, a ruthless
intergalactic conglomerate. It is up to the Doctor to uncover the secret
of the Company's head, the Collector, while Leela is sentenced to death
by steaming.

Production

In the Seventies, BBC policy generally forbade script editors from
writing for their own programme. An exception to this rule was Doctor
Who script editor Robert Holmes, who had been granted special
permission to write a limited number of serials for the show per year.
By the time planning for Season Fifteen began, Holmes had already
authored four Doctor Who adventures during his tenure (most
recently The Talons Of Weng-Chiang), and
made significant contributions to several other stories. However, his
writing had often been carried out under duress, either to replace an
abandoned script or concurrent with significant problems on other
serials.

As Holmes prepared to leave Doctor Who in early 1977, then, he
found himself with the opportunity to finally write a story which could
be given his full attention. Inspired by a non-fiction book called
The Iron Sun: Crossing The Universe Through Black Holes by Adrian
Berry, which postulated the idea of man-made suns, Holmes conceived an
adventure which would transpose Britain's former colonial ways onto a
science-fiction setting. Holmes was already working on his scripts,
bearing the title The Sun Makers, by the time approval was
granted on April 30th.

Robert Holmes was embroiled in a protracted disagreement
with Inland Revenue over income tax

One fortuitous consequence of Holmes being both a writer and script
editor for Doctor Who was that he was well aware that the
programme's principal cast might be about to grow by one member. The Invisible Enemy, which was the first
serial to go into production as part of the series' fifteenth recording
block, featured a robot dog named K·9 who proved popular with both
Holmes and producer Graham Williams. By early May, Williams had decided
to keep K·9 on as a regular character, and Holmes was able to quickly
integrate the character into The Sun Makers. John Leeson, who
provided the voice of K·9, was contracted for The Sun Makers on
May 30th.

Simultaneously, the serial was undergoing even greater changes due to
events in Holmes' personal life. At that time, he was embroiled in a
protracted disagreement with Inland Revenue over the taxes applied to
his income as a freelance writer, and was becoming increasingly
frustrated with the department's seemingly arbitrary and byzantine
regulations. Holmes saw an opportunity with The Sun Makers to
lampoon Inland Revenue, and the sphere of finances and taxation in
general. To this end, he littered his scripts with satire -- referring
to the villainous rulers of the colony as a Collector (who was a member
of an alien race called the Userers) and a Gatherer, labelling a
corridor as “P45” (an Inland Revenue form number), and
even using his nemeses' initials to inspire the name of the Inner
Retinue.

This new approach to The Sun Makers was very much to the liking
of its director, Pennant Roberts, who suggested further satirical
elements to Holmes. Roberts, who had most recently worked on
The Face Of Evil the year before, also
encouraged the inclusion of more female characters. He decided to make
Marn a woman, and excised a male member of the Others named Rashif,
giving his dialogue to Veet. Williams, however, was less keen on
presenting such a stinging spoof in the context of a family programme.
He particularly disliked the reference to the Collector's race as
“Userers”. This was briefly changed to
“Saurians” before a compromise was reached with
“Usurians”.

The Sun Makers was scheduled to be the third story in production
for Season Fifteen, and so was labelled Serial 4W. However, it was then
decided to air The Invisible Enemy as the
second serial of the season. Because this adventure was also set on a
human colony, The Sun Makers was shifted to fourth in the running
order to avoid the appearance of repetition. It would now be broadcast
after Image Of The Fendahl, the adventure
which was due to go before the cameras after The Sun Makers
wrapped production.

With Louise Jameson unhappy, thought was briefly given to
killing Leela off at the climax of The Sun
Makers

Meanwhile, Louise Jameson continued to be unhappy with aspects of her
time on Doctor Who. Although Tom Baker's attitude towards her had
improved recently, he continued to be an often moody and domineering
presence on set, and Jameson also felt that writers were frequently
ignoring the potential of the Leela character. Although Jameson was
contracted for the entirety of Season Fifteen, thought was briefly given
to having Leela killed off at the climax of The Sun Makers. This
plan was soon discarded, but although Williams was happy with Jameson's
work and wanted her to carry on with Doctor Who, he was gradually
coming to realise that a new companion might be needed for Season
Sixteen.

One of the challenges faced by Roberts' team was to find a roof which
could serve as the top of Megropolis One. To be suitable, such a
location would have to provide an empty skyline to give the correct
impression of height. Unfortunately, despite many attempts, no
appropriate building could be found in the vicinity of London. The
problem was finally solved by production assistant Leon Arnold, who
suggested filming atop the WD & HO Wills Tobacco Factory in Hartcliffe,
Bristol. Williams, who was under pressure from his superiors to control
Doctor Who's budget, was not keen on travelling that distance for
just a handful of scenes, and suggested that they instead be
accomplished in the studio via Colour Separation Overlay. However,
Roberts discovered that the Wills Tobacco Factory also offered other
useful locations (such as a very long corridor), enabling him justify
the cost of the trip.

Work at the Wills Factory spanned June 13th to 15th. In addition to the
roof and tunnels, scenes were also filmed in the lift and the roof vent.
Unfortunately, the sunshine Roberts wanted for the rooftop scenes never
materialised, with Bristol instead blanketed by mist throughout the
shoot, partly spoiling the desired effect. While at the Wills Factory,
an extra playing one of the Megro Guards fell ill, and so Wills employee
Ron Rogers agreed to take his place; Rogers' scene was later cut in
editing, however.

Additional filming then took place back in London at the Camden Deep
Tube Shelter on June 16th, 17th and 20th, involving more material in the
subways and on the main staircase. Unfortunately, Roberts' team fell
badly behind at this point, and so several sequences had to be shifted
to the studio. Model filming also took place on June 20th, at the BBC
Visual Effects Workshop.

Graham Williams was displeased that the
“consumcard” resembled an oversized BarclayCard

Studio recording then began with two days in BBC Television Centre
Studio 3. July 4th largely dealt with episode one, as well as the
closing TARDIS scene from episode four and some material in the subways
for episode two. On this day, Williams was displeased to discover that
the “consumcard” used by the Megropolis dwellers had been
crafted to resemble an oversized BarclayCard. Concerned about the
obviousness of the serial's satire and possible accusations of product
placement, Williams instructed that the prop be altered, and so
coloured tape was added to mask its origins. July 5th then saw most of
part two completed, alongside material in the pump room for part three
and the corridors for part four.

The second studio session took place from July 17th to 19th in TC6. The
first day was dedicated to scenes in the exchange hall and the
condenser, as well as those in the computer complex for episodes two and
three. Some of the part four computer complex sequences were then taped
on the 18th, alongside material in the therapy section. July 19th
involved even more material in the computer complex, as well as in
main control. Unfortunately, the delays incurred during location filming
resulted in an overrun on this final day. Even then, there was barely
enough time to record the Collector's “liquidation”. So
disappointed was visual effects designer AJ “Mitch” Mitchell
with the outcome that the experience ultimately encouraged him to leave
the BBC and for freelance work.